Machine foe grinding and polishing the exteeial suefaoes



(No ModeL) 2 Sheets8heet 1. J'. T. DUFF. MAOHINE FOR GRINDING AND POLISHING THE EXTERNAL SURFACES OF HOLLOW WARE.

Patented Sept. 6, 1.887.

\HHIU N. mm Pimlbuthagnphnr. W:

(No Model.) 2 Sheets-Sheet 2.

J. T DUFF.

' MACHINE FOR GRINDING AND POLISHING THE EXTERNAL SURFACES OF HOLLOW WARE.

UNITED STATES PATENT rrrcn.

JOHN T. DUFF, OF PITTSBUBG, PENNSYLVAXIA, ASSIGNOR TO A. M. DUFF, A. M. NEGLEY, AND H. G. HUGUS, ALL OF SAME PLACE.

MACHINE FOR GRINDING AND POLISHING THE EXTERNAL SURFACES F HOLLOW WARE.

SPECIFICATION forming part of Letters Patent No. 369,327 dated September 6, 1887.

Application filed November 11, 1886. Serial No. 219,644.

To all whom it may concern.-

Be it known that I, JOHN T. DUFF, a citizen of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Machines for Grinding and Polishing the External Surface of Hollow \Varc; and I dd'hereb'y declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use the same, reference being had to the annexed drawings,which form a part of this specification.

I My invention relates to a machine for grinding and polishing the exterior surface of hollow ware, the object being to provide a machine that will grind and polish the outside of any size or form of hollow ware; and it consists in a means for securing the object in position and a device whereby a grinding-wheel in rapid motion may reach all points of the surface to be polished, together with various other details of construction and combination of parts, as will be fully set forth hereinafter, and pointed out in the claims.

In the annexed drawings, Figure l is a front elevation of my improved exterior grinding and polishing apparatus constructed in accordance with my invention. Fig. 2 is a plan view of the same.

To put my invention into practice I provide a strong metal standard, 1, and secure the same to one end of a bed-plate, 2, by a suitable number of bolts, 3. Across the top of this standard 1, in the direction of the length of the machine, I arrange in suitable bearin gs, 4, a strong shaft, 5, having attached to one end a cylindrical form or holder, 6, of a form corresponding to the contour of the inner surface of the vessel to be ground or polished. Between the bearings it of this shaft 5 I secure a driving pulley, 7, of small diameter, which afiords a means for rotating the shaft. To the front of this standard 1, I place a sliding carriage, 8, capable of moving along a frame, 9, (attached by suitable brackets, 10, to the standard 1,) by means of a rack, 11, formed on the under side of the carriage 8, engaging with a pinion, 12, mounted on a shaft, 13, and operated by a hand- (No model.)

wheel, 14.. On the upper surface of this carriage 8, I secure a table, 15, and arrange the same in suitable slides, which will allow a limited movement at right angles to that of the carriage 8 below. The table may be moved back and. forth by a screw-shaft, 32, working in lugs 34 011 the carriage 8, and 0p erated by a hand-wheel, 33.

On the top of the table 15, I pivot an annular plate, 16, and secure the same thereto by set-screws 17, operating in circumferential 'siots 18,which will admit of the plate revolving horizontally a short distance about its pivotal point. Across the top of this annular plate 16, I secure, in proper bearings,19,a shaft, 20, having attached to one end thereof a large grinding-wheel, 21. Between the bearings 19, I attach to the shaft a tight and loose pulley, 22,which,in connection with suitable overhead belt-pulleys, gives the shaft 20 a rapid rotation on its axis. At the front of the ey lindrical holder 6, and in a direct line therewith, I erect another standard, 23, and secure the same to the base-plate in the same manner, as before described. On the top of this standard 23, I construct a frame, 24.,having suitable slides formed on the top of the same, in which I arrange a moving table or carriage, 25, and operate the same by a rack, 26, formed on the under side, a smalltoothed wheel attached to a transverse shaft, 27, and a hand-wheel, 28, as in the carriage 8, before described. To this shaft 27, I secure a suitable clutch, 29, which engages with another formed on the side of the frame 24, and serves to lock the carriage at any desired position. On the top of this sliding carriage 25, I arrange in proper bearings, 31,a shaft, 35, having an enlarged end or cap, 30, nearest the holder 6.

In operation the vessel to be ground and polished is placed over the holder 6, fitting neatly about the same. The carriage 25, conveying the shaft 29 and cap 30, is brought for ward by means of the hand-wheel 2S and pinion operating in the rack 26, which operation 9 tightly clamps the vessel to the holder 6. The

clutch 29 is now engaged, which retains the carriage 25 in that position. The holder 6 and grinding-wheel 21 are put in rapid motion in opposite or reverse directions. By means of the hand-wheel 14 the carriage S and grindingwheel 21 are slowly moved down the side of the vessel until the lower edge is reached, at which time the annular plate 16 is revolved, and thereby grinding around the corner to the edge of the clamping-disk 30, which operation finishes the article. The clutch 29 is now re leased, the carriages 8 and 25 moved back by the hand-wheels 14 and 28, respectively, and. the vessel removed.

The objects of the upper carriage or table, 15, are to take up the wear or wasting of the grinding-wheel 21 by moving the same toward the work, and also to afford a means of grinding articles of large and small diameters.

Having described my inventiomwhatlclaim 1. The combination of the supporting-frame, the grinder, the rotatable holder mounted in fixed bearings in said frame, and an adjustable clamping device consisting of the combination of the carriage 25, the headed shaft 35, having hearings in said carriage, the rack, pinion, and

hand-wheel for moving the carriage toward and from the holder, and the clutch for looking the carriage in position, substantially as set forth.

2. The combination of the supporting-frame,

the rotatable holder mounted in bearings in said frame, the adjustable clamping device arranged opposite' the end of the holder, the grinding-wheel, its carriage,the guideways or tracks running parallel with the axis of the holder and by the side thereof, in which the carriage moves, the transverse guideways in which the carriage moves toward and from the 

